To meet the needs of energy storage under high temperature and high pressure, a high‐entropy relaxor ferroelectric ceramic, La‐modified (Bi0.2Na0.2Ba0.2Sr0.2Ca0.2)TiO3 is prepared, which has excellent thermal and mechanical stability. At the wide temperature range of 327–689 K (tan δ < 0.01) and below ≈7 GPa, the material shows extraordinary functional performance. Comprehensive study indicates that the ceramic possesses a single‐phase cubic perovskite structure, and as the pressure increases, the material undergoes a transition at ≈8 GPa, in which enormous large grains crack into smaller grains, but the space group does not change. In addition, with further compression, the grains begin to rotate and re‐orientate at ≈9 GPa. Based on the investigations, it is considered that the suitable doping of multiple cations can effectively improve the stability of ceramics, and it also paves the experimental way to further study thermally and mechanically stable high‐entropy ceramics.

中文翻译：

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高熵 La-(Bi0.2Na0.2Ba0.2Sr0.2Ca0.2)TiO3 陶瓷在 327–689 K 和高达 7 GPa 范围内具有超稳定介电性能

为了满足高温高压下储能的需要，一种La改性的高熵弛豫铁电陶瓷（Bi0.2钠0.2巴0.2锶0.2钙0.2)二氧化钛3制备而成，具有优异的热稳定性和机械稳定性。在 327–689 K 的宽温度范围内（tanδ< 0.01) 且低于 ≈7 GPa，该材料表现出非凡的功能性能。综合研究表明，该陶瓷具有单相立方钙钛矿结构，随着压力的增加，材料在约8 GPa时发生转变，巨大的大晶粒破裂成更小的晶粒，但空间群没有变化。此外，随着进一步压缩，颗粒开始旋转并在约 9 GPa 时重新定向。研究认为，多种阳离子的适当掺杂可以有效提高陶瓷的稳定性，也为进一步研究热稳定和机械稳定的高熵陶瓷铺平了实验道路。